This version has the Takahashi-Style M72x1mm rear female thread, enabling extra spacing of 74.4mm to the sensor, so you can fit more accessories like filter wheels and OAGs between camera and sensor.

It converts your 115mm F7 ED Triplet into a high resolution astrograph with fast F5.6 focal ratio and 728mm focal length.

Altair PlanoStar Reducer features and instructions:

• The reducer has an M72x1.0mm "Takahashi" rear female thread. Therefore you will require an M72x1mm male to M48 (or T2) male adaptor to connect your camera or filter wheel. The ideal distance to CCD sensor from the rear-most of the rear shoulder is 74.4mm (excluding the inner thread). Tests indicate that the flattener is tolerant about 1.0mm either side of this distance. The smaller your CCD chip, the less critical spacing becomes.
• The flattener is threaded directly to the rear of the focuser. Simply remove the 2" push-fit adaptor from your focuser and screw the flattener into the rear of the 3.7" focuser by means of the M92 rear thread.
• Corrects for field curvature and improves images taken with cameras up to APS size, allowing more of the photographic field to be utilised. It will also work with a full frame sensor, however you may need to crop the outer edges slightly, which in deep-sky imaging is frequently done anyway, due to minor alignment issues between frames.
• High quality multi-coatings on all surfaces ensure maximum transmission and almost zero reflections, however it is good practise to place any filters as far from the rear lens of the flattener as possible and as close to the camera sensor as possible. We recommend the Altair Magnetic filter holder with appropriate threads (search code "MAGF") for this purpose. Please click here for camera and reducer spacing instructions. (opens new window). To connect a Canon DSLR you need a Canon/Nikon M48 DSLR Adaptor (available separately).